Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quantas equipes da NHL existem na área de Phoenix, Arizona?
 ###Tabelas: CREATE TABLE political_division (political_division_id AUTO_INCREMENT PRIMARY KEY, City district VARCHAR, Area km² VARCHAR, Population 2007 census(hab) VARCHAR, Housing (2007) VARCHAR, Density (hab/km²) VARCHAR, Elevation msl VARCHAR) CREATE TABLE dvd_and_blu-ray_releases (dvd_and_blu-ray_releases_id AUTO_INCREMENT PRIMARY KEY, Release Title VARCHAR, Series VARCHAR, No. of DVDs VARCHAR, No. of Blu-ray Discs VARCHAR, Release Date VARCHAR, Episode No. VARCHAR, Region No. INT, Released by VARCHAR) CREATE TABLE overview_by_city (overview_by_city_id AUTO_INCREMENT PRIMARY KEY, Metropolitan Area VARCHAR, Media Market Ranking INT, Hosted 4 teams since INT, NFL Team(s) VARCHAR, MLB Team(s) VARCHAR, NBA Team(s) VARCHAR, NHL Team(s) VARCHAR) CREATE TABLE merchant_ships (merchant_ships_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Flag VARCHAR, Cargo VARCHAR, Fate VARCHAR, Date of attack VARCHAR) CREATE TABLE repeat_winners (repeat_winners_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Name VARCHAR, Country VARCHAR, Wins INT, Years VARCHAR)  
SELECT COUNT NHL Team(s) FROM overview_by_city WHERE Metropolitan Area = Phoenix, Arizona